Urine formation mechanism has the following 4 steps. Arrange them systematically.
i) Tubular reabsorption
ii) Glomerular filtration
iii) Concentration of urine
iv) Tubular secretion
A) (i), (ii), (iii), (iv)
B) (iv), (iii), (ii), (i)
C) (iii), (ii), (i), (iv)
D) (ii), (i), (iv), (iii)